A printing group of a rotary printing press having at least one transfer cylinder and at least one forme cylinder is known from WO 01/39977 A1. The transfer cylinder has a groove for receiving either one or several printing blankets, and the forme cylinder has at least two grooves, which are arranged one behind the other in the circumferential direction, for receiving one or several printing formes. At least one of the grooves of the forme cylinder is at least partially covered by a printing forme. That at least partially covered groove of the forme cylinder rolls off on the area of the groove of the cooperating transfer cylinder intended for receiving one or several printing blankets. The ends of the printing formes can be arranged, offset with respect to each other, in different grooves, or the forme cylinder can have at least two printing formes arranged side-by-side in the axial direction, or can have several printing formes arranged one behind the other in the circumferential direction. In the case of several printing formes arranged over the entire circumference, these can also be arranged with their ends alternatingly arranged offset with respect to each other.
DE 22 20 652 A1 describes a device for fastening flexible printing plates on the plate cylinder of a rotary printing press. The device has a pair of bracing-clamping cheeks, which are arranged on the same shaft and which are arranged in a cylinder groove in the cylinder body, and are pivotable around a shaft that is extending parallel with the cylinder axis over the entire length of the cylinder. A bracing-clamping cheek pair consists of a bracing cheek and a clamping cheek, wherein the bracing cheek, as well as the clamping cheek working together with it, are seated, pivotable around a shaft which is parallel with the axis and which can be actuated from the front end of the cylinder. In the preferred embodiment described, four bracing-clamping cheek pairs are alternatingly arranged, once on one half of the cylinder length and again on the other half of the cylinder length. To adapt this prior device to printing plates of different format widths, a short bracing-clamping cheek pair is arranged as an extension element between two adjoining bracing-clamping cheek pairs in such a way that it can be connected in the cylinder body with the adjacent bracing-clamping cheek pairs and thus can be pivoted in the same way as the bracing-clamping cheek pairs. Two coaxially arranged connecting shafts are provided in each cylinder groove, which shafts can be rigidly connected with a bracing-clamping cheek pair, that is arranged in one half of the cylinder length, and which shafts permit a torque to be transmitted from the front end, which is a part of the other half of the cylinder, to the bracing-clamping cheek pair which is connected with the connecting shafts. Accordingly, the connecting shafts are pivotably seated in the cylinder groove in the same way as are the bracing-clamping cheek pair connected with them.
A cylinder pair of a rotary printing press, with a 6/2 plate cylinder and with a printing blanket cylinder, is known from DE 25 28 008 A1. A center set of printing plates is arranged on the plate cylinder and is deliberately offset, at an angle other than 90°, from the two outer sets of printing plates positioned at the ends of the plate cylinder. The center printing blanket on the printing blanket cylinder is arranged deliberately offset at an angle other than 90° from the outer sets of printing blankets at the ends of the blanket cylinder. The ends of the dressings which are not angled off and which rest on the respective cylinder, are held by holding devices which are movable in wide cylinder grooves. Ends of dressings, which ends face each other, form a gap between themselves, which gap extends over the width of these dressings.
A device for bracing and/or for clamping flexible plates with angled-off suspension legs, which legs project into a fastening slit of a cylinder used for supporting the plates, is known from DE 199 24 786 A1. The fastening slit is connected with an axis-parallel cylinder groove in the cylinder radial direction. A base body, which is open in the direction toward the fastening slit, is arranged in the cylinder groove. Movable bracing and/or clamping elements are provided in the interior of the base body. The base body can consist of several shorter base bodies, which can be coupled together. The base body or bodies, arranged in a row in the cylinder groove, are connected with each other, fixed against relative rotation, by, for example, a tooth arrangement. A first and a last base body are each connected, fixed against relative rotation, with an end coupling element, whose parts which cover the cylinder groove are fastened on the flanks of the cylinder, for example by the use of screws.
A cylinder of a web-fed rotary printing press is known from DE 199 01 574 A1. A shell of the cylinder is divided, over its length, into adjoining sections, and an opening is provided in each section. This type of construction of a cylinder is not suitable for use in arranging several dressings on the shell of the cylinder along its circumference.
Such a cylinder of single circumference is also known from JP 10-071 694 A. The forme cylinder and the transfer cylinder are arranged in the printing group in such a way that an opened section of the forme cylinder rolls off on a closed section of the transfer cylinder, and vice versa.
A printing group cylinder, with a groove with alternatingly opened and closed areas arranged on the shell, is known from DE 198 54 495 A1. Tongues of a printing forme to be mounted on the printing group cylinder extend into the opened areas.
A cylinder for printing presses is known from DE 696 04 065 T2. A groove, which is open toward the shell, is closed by an insertion piece, which terminates flush with the shell.
A cylinder of single circumference for printing presses is known from CH 345 906 A. Four dressings are arranged, side-by-side, on the cylinder in its axial direction. Each of the dressings is fastened in a bracing groove which is open toward the shell of the cylinder. The bracing grooves of adjacent dressings are arranged offset in respect to each other along the circumference of the cylinder.